1. Field of the Invention
The present invention relates generally to a medical device and, more particularly, to a medical device with a magnetically-responsive control switch.
2. Related Art
The use of medical devices to provide therapy to individuals for various medical conditions has become more widespread as the advantages and benefits such devices provide become more widely appreciated and accepted throughout the population. For example, devices such as acoustic prostheses, implantable pacemakers, defibrillators, organ assist or replacement devices, and other medical devices, have been successful in performing life saving and/or lifestyle enhancement functions for a number of years.
Some medical devices include one or more sensors, processors, controllers, pumps, actuators, or other functional components that are permanently or temporarily implanted in a patient. Many such implantable devices require power and/or require communications with external systems that are part of or operate in conjunction with such implanted components. One common approach to provide for the transcutaneous transfer of power and/or communications with an implantable component is via a transcutaneous transfer system.
One type of implantable medical device that may include a transcutaneous transfer system is an acoustic prosthesis cochlear™ implants provide the benefit of hearing to individuals suffering from severe to profound hearing loss. Hearing loss in such individuals is due to the absence or destruction of the hair cells in the cochlea which transduce acoustic signals into nerve impulses. Cochlear™ implants essentially simulate the cochlear hair cells by directly delivering electrical stimulation to the auditory nerve fibers. This causes the brain to perceive a hearing sensation resembling the natural hearing sensation normally delivered to the auditory nerve.
Conventional cochlear™ implants primarily include external components directly or indirectly attached to the body of the patient (sometimes referred to herein as the recipient), and internal components which are implanted in the patient. The external components typically enable the recipient to control a number of operational settings of the device, through manipulations one or more switches.
For example, the external components often include a speech processor unit that has an on/off switch which is manipulated by a user. Due to its small dimensions, the switch may be difficult to operate particularly for the elderly and disabled. Further, the switch can allow the ingress of moisture into the interior of the speech processor unit resulting in its destruction. The switch can also easily be corroded by moisture rendering it unreliable and unsuitable for use in humid environments. In addition, certain types of switches may be susceptible to breakage resulting from mechanical fatigue.